flugelhorn vs brass instrument

flugelhorn and brass instrument both are nouns.

Word	Noun	Adjective	Verb	Adverb
flugelhorn	Yes	No	No	No
brass instrument	Yes	No	No	No

As nouns, brass instrument is a hypernym of flugelhorn; that is, brass instrument is a word with a broader meaning than flugelhorn:

flugelhorn: a brass instrument resembling a cornet but with a wider bore
brass instrument: a wind instrument that consists of a brass tube (usually of variable length) that is blown by means of a cup-shaped or funnel-shaped mouthpiece

Other hypernyms of flugelhorn include brass.

flugelhorn (noun)	brass instrument (noun)
a brass instrument resembling a cornet but with a wider bore	a wind instrument that consists of a brass tube (usually of variable length) that is blown by means of a cup-shaped or funnel-shaped mouthpiece